// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/base/upload_file_element_reader.h"

#include <stdint.h>

#include <limits>

#include "base/files/file_util.h"
#include "base/files/scoped_temp_dir.h"
#include "base/run_loop.h"
#include "base/threading/thread_task_runner_handle.h"
#include "net/base/io_buffer.h"
#include "net/base/net_errors.h"
#include "net/base/test_completion_callback.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "testing/platform_test.h"

namespace net {

class UploadFileElementReaderTest : public PlatformTest {
protected:
    void SetUp() override
    {
        PlatformTest::SetUp();
        // Some tests (*.ReadPartially) rely on bytes_.size() being even.
        const char kData[] = "123456789abcdefghi";
        bytes_.assign(kData, kData + arraysize(kData) - 1);

        ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());

        ASSERT_TRUE(base::CreateTemporaryFileInDir(temp_dir_.path(),
            &temp_file_path_));
        ASSERT_EQ(
            static_cast<int>(bytes_.size()),
            base::WriteFile(temp_file_path_, &bytes_[0], bytes_.size()));

        reader_.reset(new UploadFileElementReader(
            base::ThreadTaskRunnerHandle::Get().get(), temp_file_path_, 0,
            std::numeric_limits<uint64_t>::max(), base::Time()));
        TestCompletionCallback callback;
        ASSERT_EQ(ERR_IO_PENDING, reader_->Init(callback.callback()));
        EXPECT_EQ(OK, callback.WaitForResult());
        EXPECT_EQ(bytes_.size(), reader_->GetContentLength());
        EXPECT_EQ(bytes_.size(), reader_->BytesRemaining());
        EXPECT_FALSE(reader_->IsInMemory());
    }

    ~UploadFileElementReaderTest() override
    {
        reader_.reset();
        base::RunLoop().RunUntilIdle();
    }

    std::vector<char> bytes_;
    std::unique_ptr<UploadElementReader> reader_;
    base::ScopedTempDir temp_dir_;
    base::FilePath temp_file_path_;
};

TEST_F(UploadFileElementReaderTest, ReadPartially)
{
    const size_t kHalfSize = bytes_.size() / 2;
    ASSERT_EQ(bytes_.size(), kHalfSize * 2);
    std::vector<char> buf(kHalfSize);
    scoped_refptr<IOBuffer> wrapped_buffer = new WrappedIOBuffer(&buf[0]);
    TestCompletionCallback read_callback1;
    ASSERT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback1.callback()));
    EXPECT_EQ(static_cast<int>(buf.size()), read_callback1.WaitForResult());
    EXPECT_EQ(bytes_.size() - buf.size(), reader_->BytesRemaining());
    EXPECT_EQ(std::vector<char>(bytes_.begin(), bytes_.begin() + kHalfSize), buf);

    TestCompletionCallback read_callback2;
    EXPECT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback2.callback()));
    EXPECT_EQ(static_cast<int>(buf.size()), read_callback2.WaitForResult());
    EXPECT_EQ(0U, reader_->BytesRemaining());
    EXPECT_EQ(std::vector<char>(bytes_.begin() + kHalfSize, bytes_.end()), buf);
}

TEST_F(UploadFileElementReaderTest, ReadAll)
{
    std::vector<char> buf(bytes_.size());
    scoped_refptr<IOBuffer> wrapped_buffer = new WrappedIOBuffer(&buf[0]);
    TestCompletionCallback read_callback;
    ASSERT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback.callback()));
    EXPECT_EQ(static_cast<int>(buf.size()), read_callback.WaitForResult());
    EXPECT_EQ(0U, reader_->BytesRemaining());
    EXPECT_EQ(bytes_, buf);
    // Try to read again.
    EXPECT_EQ(0,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback.callback()));
}

TEST_F(UploadFileElementReaderTest, ReadTooMuch)
{
    const size_t kTooLargeSize = bytes_.size() * 2;
    std::vector<char> buf(kTooLargeSize);
    scoped_refptr<IOBuffer> wrapped_buffer = new WrappedIOBuffer(&buf[0]);
    TestCompletionCallback read_callback;
    ASSERT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback.callback()));
    EXPECT_EQ(static_cast<int>(bytes_.size()), read_callback.WaitForResult());
    EXPECT_EQ(0U, reader_->BytesRemaining());
    buf.resize(bytes_.size()); // Resize to compare.
    EXPECT_EQ(bytes_, buf);
}

TEST_F(UploadFileElementReaderTest, MultipleInit)
{
    std::vector<char> buf(bytes_.size());
    scoped_refptr<IOBuffer> wrapped_buffer = new WrappedIOBuffer(&buf[0]);

    // Read all.
    TestCompletionCallback read_callback1;
    ASSERT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback1.callback()));
    EXPECT_EQ(static_cast<int>(buf.size()), read_callback1.WaitForResult());
    EXPECT_EQ(0U, reader_->BytesRemaining());
    EXPECT_EQ(bytes_, buf);

    // Call Init() again to reset the state.
    TestCompletionCallback init_callback;
    ASSERT_EQ(ERR_IO_PENDING, reader_->Init(init_callback.callback()));
    EXPECT_EQ(OK, init_callback.WaitForResult());
    EXPECT_EQ(bytes_.size(), reader_->GetContentLength());
    EXPECT_EQ(bytes_.size(), reader_->BytesRemaining());

    // Read again.
    TestCompletionCallback read_callback2;
    ASSERT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback2.callback()));
    EXPECT_EQ(static_cast<int>(buf.size()), read_callback2.WaitForResult());
    EXPECT_EQ(0U, reader_->BytesRemaining());
    EXPECT_EQ(bytes_, buf);
}

TEST_F(UploadFileElementReaderTest, InitDuringAsyncOperation)
{
    std::vector<char> buf(bytes_.size());
    scoped_refptr<IOBuffer> wrapped_buffer = new WrappedIOBuffer(&buf[0]);

    // Start reading all.
    TestCompletionCallback read_callback1;
    EXPECT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer.get(), buf.size(), read_callback1.callback()));

    // Call Init to cancel the previous read.
    TestCompletionCallback init_callback1;
    EXPECT_EQ(ERR_IO_PENDING, reader_->Init(init_callback1.callback()));

    // Call Init again to cancel the previous init.
    TestCompletionCallback init_callback2;
    EXPECT_EQ(ERR_IO_PENDING, reader_->Init(init_callback2.callback()));
    EXPECT_EQ(OK, init_callback2.WaitForResult());
    EXPECT_EQ(bytes_.size(), reader_->GetContentLength());
    EXPECT_EQ(bytes_.size(), reader_->BytesRemaining());

    // Read half.
    std::vector<char> buf2(bytes_.size() / 2);
    scoped_refptr<IOBuffer> wrapped_buffer2 = new WrappedIOBuffer(&buf2[0]);
    TestCompletionCallback read_callback2;
    EXPECT_EQ(ERR_IO_PENDING,
        reader_->Read(
            wrapped_buffer2.get(), buf2.size(), read_callback2.callback()));
    EXPECT_EQ(static_cast<int>(buf2.size()), read_callback2.WaitForResult());
    EXPECT_EQ(bytes_.size() - buf2.size(), reader_->BytesRemaining());
    EXPECT_EQ(std::vector<char>(bytes_.begin(), bytes_.begin() + buf2.size()),
        buf2);

    // Make sure callbacks are not called for cancelled operations.
    EXPECT_FALSE(read_callback1.have_result());
    EXPECT_FALSE(init_callback1.have_result());
}

TEST_F(UploadFileElementReaderTest, Range)
{
    const uint64_t kOffset = 2;
    const uint64_t kLength = bytes_.size() - kOffset * 3;
    reader_.reset(new UploadFileElementReader(
        base::ThreadTaskRunnerHandle::Get().get(), temp_file_path_, kOffset,
        kLength, base::Time()));
    TestCompletionCallback init_callback;
    ASSERT_EQ(ERR_IO_PENDING, reader_->Init(init_callback.callback()));
    EXPECT_EQ(OK, init_callback.WaitForResult());
    EXPECT_EQ(kLength, reader_->GetContentLength());
    EXPECT_EQ(kLength, reader_->BytesRemaining());
    std::vector<char> buf(kLength);
    scoped_refptr<IOBuffer> wrapped_buffer = new WrappedIOBuffer(&buf[0]);
    TestCompletionCallback read_callback;
    ASSERT_EQ(
        ERR_IO_PENDING,
        reader_->Read(wrapped_buffer.get(), kLength, read_callback.callback()));
    EXPECT_EQ(static_cast<int>(kLength), read_callback.WaitForResult());
    const std::vector<char> expected(bytes_.begin() + kOffset,
        bytes_.begin() + kOffset + kLength);
    EXPECT_EQ(expected, buf);
}

TEST_F(UploadFileElementReaderTest, FileChanged)
{
    base::File::Info info;
    ASSERT_TRUE(base::GetFileInfo(temp_file_path_, &info));

    // Expect one second before the actual modification time to simulate change.
    const base::Time expected_modification_time = info.last_modified - base::TimeDelta::FromSeconds(1);
    reader_.reset(new UploadFileElementReader(
        base::ThreadTaskRunnerHandle::Get().get(), temp_file_path_, 0,
        std::numeric_limits<uint64_t>::max(), expected_modification_time));
    TestCompletionCallback init_callback;
    ASSERT_EQ(ERR_IO_PENDING, reader_->Init(init_callback.callback()));
    EXPECT_EQ(ERR_UPLOAD_FILE_CHANGED, init_callback.WaitForResult());
}

TEST_F(UploadFileElementReaderTest, InexactExpectedTimeStamp)
{
    base::File::Info info;
    ASSERT_TRUE(base::GetFileInfo(temp_file_path_, &info));

    const base::Time expected_modification_time = info.last_modified - base::TimeDelta::FromMilliseconds(900);
    reader_.reset(new UploadFileElementReader(
        base::ThreadTaskRunnerHandle::Get().get(), temp_file_path_, 0,
        std::numeric_limits<uint64_t>::max(), expected_modification_time));
    TestCompletionCallback init_callback;
    ASSERT_EQ(ERR_IO_PENDING, reader_->Init(init_callback.callback()));
    EXPECT_EQ(OK, init_callback.WaitForResult());
}

TEST_F(UploadFileElementReaderTest, WrongPath)
{
    const base::FilePath wrong_path(FILE_PATH_LITERAL("wrong_path"));
    reader_.reset(new UploadFileElementReader(
        base::ThreadTaskRunnerHandle::Get().get(), wrong_path, 0,
        std::numeric_limits<uint64_t>::max(), base::Time()));
    TestCompletionCallback init_callback;
    ASSERT_EQ(ERR_IO_PENDING, reader_->Init(init_callback.callback()));
    EXPECT_EQ(ERR_FILE_NOT_FOUND, init_callback.WaitForResult());
}

} // namespace net
